Submission #435882

#	Time	Username	Problem	Language	Result	Execution time	Memory
435882		training4usaco	Knapsack (NOI18_knapsack)	C++11	100 / 100	145 ms	3664 KiB

knapsack

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

#define fi first
#define se second
#define INF 1000000009

bool comp(pair<int,int> a, pair<int,int> b) {
    return a.fi > b.fi;
}

int main() {
    int s, n;
    cin >> s >> n;

    vector<vector<pair<int,int>>> val(s + 1);

    for(int i = 0; i < n; ++i) {
        int v, w, k;
        cin >> v >> w >> k;
        val[w].push_back(make_pair(v, k));
    }

    for(int i = 1; i <= s; ++i) {
        sort(val[i].begin(), val[i].end(), comp);
    }

    vector<int> dp(s + 1, -INF);
    dp[0] = 0;

    for(int i = 1; i <= s; ++i) {
        int used_space = 0;
        for(pair<int,int> item : val[i]) {
            for(int c = 1; c <= item.se; ++c) {
                used_space += i;
                for(int leftover_space = s; leftover_space >= used_space; --leftover_space) {
                    dp[leftover_space] = max(dp[leftover_space], dp[leftover_space - i] + item.fi);
                }
                if(used_space > s) {
                    break;
                }
            }
            if(used_space > s) {
                break;
            }
        }
    }

    int answer = 0;
    for(int i = 1; i <= s; ++i) {
        answer = max(answer, dp[i]);
    }
    cout << answer << endl;
}

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 27 / 27